Monday, July 1, 2013

Archimedes yelling Eureka - maybe


M.I.T research led by Wei Pan concluded that productivity and innovation in urban areas grow at roughly the same rate as population, largely because the greater density of people living in a city increases the opportunities for personal interactions and exposure to different ideas. Put simply, living in a city makes us more innovative.


The idea that Archimedes yelling “Eureka” as he ran naked through the streets of Syracuse is a nice visual for the concept of discovery, albeit unlikely given the story first appeared in a book two centuries after the Greek scholar had died. The story does however feed the fantasy of discovery as a solitary and sudden experience.

Wei Pan, analyzed all kinds of factors to tabulate the “social-tie density” of different cities–that’s the average number of people each resident will interact with personally. 

They looked at everything from the number of call partners with whom a cellphone user will end up sharing a cell tower to the number of people connecting through location-based social networks like Foursquare to the contagion rates of diseases spread only through personal contact. And they found that the higher a city’s social-tie density, the higher its levels of productivity and patents awarded.

Tuesday, February 26, 2013

Consequence-free photo sharing?


A friend of mine asked me the other day if I was using Snapchat yet – she wanted to send me a pic. I said no, but it didn’t take me long to download the free app. 


I’d heard about the app, thought it was a neat idea, but also thought it might lull people into a false sense of security particularly with kids and sexting. After all the app has been touted as a "consequence-free" photo/video sharing platform by many.

For those not familiar with this app - users can send photos and videos, called Snaps to individuals or groups with a an expiration time between one second and 10 seconds before the content dissolves.

During this duration, the recipient must maintain contact with the device's touchscreen designed to inhibit taking a screenshot. If recipients were to take a screenshot the app notifies the sender.

So how safe is it? Well it turns out that a college student Raj Vir has found a way for recipients to "easily save screenshots of 'snaps' in a few simple steps.

Here are those steps

  • While viewing a SnapChat photo, take a screenshot by pressing the home and power button at the same time, while making sure to continue holding on the screen in order to ensure that the picture gets captured.
  • After taking the screenshot, the photo won’t show on the screen and you will be brought back to your list of snaps.
  • Before the photo expires, double tap the home button to bring up the multitasking bar. Once you’ve brought that up, SnapChat won’t recognize your screenshot.


Tuesday, February 12, 2013

God's existence and mathematicians thousands of years hence


The most beautiful equation ever

It is said that one day, when the great German mathematician Leonhard Euler was at the Court of Catherine the Great, a friend asked him for a proof of the existence of God. Euler is supposed to have replied with what is now called the Euler Identity and then essentially said Q.E.D.


Euler's Identity is indeed beautiful because the five parts of the equation come from vastly different origins, and each with roles in mathematics that can’t be overstated and that they should be connected by such a simple relationship, is simply stunning. 

One would have to think that Euler’s identity will appear, to the arbitrarily advanced mathematicians thousands of years hence, to remain as beautiful and stunning as the day it was first written.

Monday, February 11, 2013

The Bank That Ran Out of Money



Over the Christmas break I started watching the tale of the RBS, Inside the Bank That Ran Out of Money. This is the story of how one of the most successful banks in the world ran up the biggest corporate loss in history, a loss of €24.1Billion. 

There have been many reasons offered for the cause of the 2007 and 2008 global financial crisis including availability of easy access to loans for subprime borrowers, overvaluation of bundled sub-prime mortgages as well as the result of "high risk, complex financial products. It is the creation and evaluation of high complex products that caught my interest. Basically mortgage derivative products, where risky mortgages were packaged with more traditionally secure mortgages and sold to corporate investors and other banks as secure investment products.

The documentary RBS, Inside the Bank That Ran Out of Money interviewed an ex-executive of the bank who described how some of the best mathematician and physicist were running complex financial models to evaluate risk and predict earnings.

I wanted to look at the type of the mathematics and modelling that is used in the financial sector. Amongst numerous factors, some say the Black-Scholes equation was the mathematical justification for the trading that ultimately helped plunge the world's banks into catastrophe. The equation, brainchild of economists Fischer Black and Myron Scholes, provided a rational way to price a financial contract when it still had time to run. And the equation itself can’t be blamed for the credit crunch.

The formula is fine if it is to be used sensibly and abandoned when market conditions become inappropriate. The trouble was its potential for abuse. It allowed derivatives to become commodities that could be traded in their own right. Courtesy of Wikipedia here is the equation.